Weft cutter for looms



NOV. 5, 1940. K, SCHWABE 2,220,665

WEFT CUTTER FOR LOOMS Filed Aug. l0, 1937 4 Sheets-Sheet l www, 24

NOV. 5, 1940. K SCHWABE 2,220,665

WEFT CUTTER FOR LOOMS Filed Aug. l0, 1937 4 Sheets-Sheet 2 Nov. 5, 1940. K. scHwABE WEFT CUTTER FOR LOOMS Filed Aug. lO, 1937 4 Sheets-Sheet I5 L AAAAAAA N v [7? me 77 far NOV. 5, 1940. K, SCHWABE 2,220,665

WEFT CUTTER FOR LOOMS Filed Aug. l0, 1937 4 Sheets-Shea?l 4 E50 enfer.

lil/R7 SCHWA BE E770/@NEP Patented Nov. 5, 1940 UNITED STATES PATENT OFFICE i Application August 1`o, 1937, serial No. 158,299

Y In Germany August 12, 1936 2Clalms.

old weft extending from the selvage to an ex-v hausted shuttle and the new weft extending from the selvage to the usual weft end holder is comparatively simple since the two operations are w eiected on consecutive picks. In the case of a multi-shuttle loom having a series of drop-boxes on the replenishing side the process is more complicated because a newly replenished shuttle may not come into action immediately after replenish- 15 ment but may remain, for an indefinite number of picks, on the replenishing side.

It is an object of the present invention to provide a cutter for mechanical looms having selfactuating bobbin or shuttle exchange, particu- 20 larly for weaving looms provided with a bilateral shuttle exchange, characterized by that the cutter release is controlled by two shafts, one of which rotates at the speed of the crankshaft for the loom and the other of which is put into ro- 26 tation during the bobbin or shuttle exchange, the respective times or periods of release being regulated by connecting instrumentalities (such as, for example, excentrics, cam discs and contact breakers) and eventually determined by positions a of the shuttle box on the exchange side.

It is a further object of the present invention to provide a cutter for mechanical looms, wherein the said two shafts rotate independently of one another for controlling movements of the cutter.

35 A still further object of the invention is to provide improved thread-cutting means for an automatic weft-replenishing loom, especially one provided with a series of drop-boxes at the relatch devices carried by the drop-boxes at thev replenishing end of the loom.

The cutter comprises three parts or groups of 50 parts, rotatable independently of one another, one part or group acting as a thread lifter and raising the inactive weft or wefts clear of the cutter blade, the second part or group forming a thread holder and the third a cutterf 55, A still further object of the invention is a cutter for mechanical looms with self-'actuating bobbin or shuttle exchange, in which the control of the cutter takes place at rst from the camshaft which initiates the bobbin or shuttle exchange or completes it, and then from the gear pawl '5 which is attached to the shuttle box. By means of the bobbin or shuttle exchange, the gear pawl, which is arranged at the shuttle box compartment which isof the same height as they slay beam, is reversed. The release of the cutter is l0 suitably eil'ected by means of an electro-magnet which is connected, rst through a contact breaker on the cam shaft and then through a contact breaker on the crankshaft or on a. shaft driven from the latter. Preferably the cutter i consists of three parts which are rotatable independently of each other about a common axis on the slay, or of groups of parts of which one acts as thread lifter and raises the threads which run through the other shuttle box compartment and removes them from the reach of the cutter blade, while a second forms a thread holder and a third acts as cutter.

The accompanying drawings show by way of example one embodiment of the invention:

Fig. 1 shows a vertical section of the cutter;

Fig. 2 a lateral section;

Fig. 3 a base plan of the device;

v Figs. 4, 4a, 4b, 4c, 4d, 4e, and 4f indicate the separate parts of the thread cutter and holder device:

Fig. 5 illustrates the position of the cutter parts after actuation of the thread lifter;

Fig. 6 shows the position of the cutter parts after closing the thread holder device, while Fig. '7 shows the cutter during the cutting operation;

Fig. 8 shows in lateral section the arrangement of the shuttle boxes and the gear appliance for actuating the cutter, o

Fig. 9 shows a ,lateral view of the structure of Fig. 8, viewed from the left in Fig. 8.

Fig. 10 is an isometric view of structure shown in Fig. 5.

Referring to the drawings, a shaft I rests rotatably on the slay I in bearings 2 and 3. This shaft is shown detached in Fig. 4f. It has a squared part 5, a collar 6 and on the opposite side of the collar to the part 5 a key V'|. One of the cutter blades 8 is slipped on to the squared 50 part 5 and is pressed against the collar 6 by means of a. pressure spring 9. 0n the collar 8 there is loosely mounted another or colmter cutter blade` ll on the boss of which is a toothed wheel l0, whilst the key I holds a clamp ilnger lI3 tightly on the shaft 4. Adjacent the finger I3 there is provided a counter nger I5 which is rotatable loosely on the shaft. The finger I5 has arprojection I6 of triangular section which fits into/a groove I1 of similar section in the finger I3. Its purpose is to hold the thread during pressing of counter linger I5 against clamp nger I3. The counter finger I5 has also a notch I8 for the purpose of preventing slipping down of the thread, and its boss carries a toothed segment I4. The boss of nnger I3 has also a toothed segment I2.

Av shaft 2| mounted in bearings I8 and 20 on the slay carries the toothed wheels 23 and 25, whilst toothed wheels 22 and 24 are loosely rotatable on shaft 2|. 'I'he toothed segment I4 of flnger I5 meshes with toothed wheel 22, whilst toothed wheel. 24 engages with the toothed segment I2 of the finger I3 and the toothed wheel 25 meshes with segment I0 of part II. The toothed wheels 22, 23 and 24 are connected respectively with three rack bars 26, 21 and 28 which are conducted in guides 29 and 30. These rack bars are drawn toward the right (Fig. 2) by springs 3| a, b, c; when at rest they are located respectively by three locking levers 32, 33, 34. 'Ihe locking levers 32, 33, 34 aregcarried by a common axle or spindle 31 rotatable in bearings 35 and 36 on slay I. 'I'he lever 32 is adapted to lie in the path of a nose 4| o rack bar 26, while an arm 45 associated with the lever is connected slay I.

with the armature 46 of an electro-magnet 41 and is rotated clockwise by a spring 38. The locking lever 33 is adapted to lie in the path of a nose 42 on the rack bar 21 and secures the latter in its position of rest whilst said lever 33 is drawn upwards by a spring 39. The locking lever 34 is adapted to lie in the path of a shoulder 43 of the rack bar 26 and is controlled, by way of example, by means of a draw hook 46 by the movement of the slay in such a manner that at tl e appropriate point in the movement it removes the lever from engagement with the shoulder 43. The rack bar 21 has also a nose 49 which can engage with a short lever 50 on a shaft 5I resting rotatably on The rack bar 26 has an inclined part 44 by means of which the locking lever 33 can be pressed down. The rack bars 21 and 28 have respective shoulders 52, 53 which are adapted to contact with the guide 30.

The shuttle box 52 (Fig. 8) has a vertical wall 53. Bolts 55 a, b, c extending through this wall 53 carry respective stepped latches 54a, 54h, 54e and bolts 51 a, b, c which cooperate with the latches. The stepped latches are connected with their respective locking pawls by springs 58a, 56h and 58e which tend to turn the locking pawls in an anti-clockwise direction and the stepped latches in a clockwise direction. The stepped latches have projecting pins 59a, 58h, 59e and the locking pawls have projections 60a, 60h and 60e. A three-armed lever 62 is carried by a stud 6I on the slay. One arm of which has guides 63' and 63" into which pins 59a, 53h, 59e can t. A second arm 64 of the lever is adapted to actuate a switch 65 and its third arm 66 a roller 61. The shaft 5I has a lever 68 adapted to engage the projections 60a, 60h, 6I|c of the locking pawls.

The gear shaft 69 by which weft replenishment is initiated or effected, rotates, by way of example, in an anti-clockwise direction, when the feeler mechanism of the loom indicates weft exhaustion. A cam 16 rests upon the shaft 69 and can engage with lever 66 through its roller piece 61, and also a second cam 1I with two cam portions a: and y, which actuate a switch 12. The cam 14 with two cams t and u rests upon ashaft 13 which is coupled positively with a crankshaft of the loom for the purpose of actuating the switch 15.

The operation of the device is as follows: when the slay I comes forward, the three rack bars 26, 21, 28 are pressed rearwardly against the acparts 6, II, I3 and I5 enter a recess (not indicated) in the slay I so that the shuttle may pass'/ over them. If now the slay moves away from the breast beam 11 and the loom continues to operate normally, the rack bars 26, 21, 26 are held by the locking levers 32, 33, 34 and the cutter remains at rest during one full revolution of the crank.

If however the feeler mechanism, not illustrated, indicates weft exhaustion, the gear shaft 69 is made to rotate by means of devices not here described and which are known in the art. The cam 1I closes the switch 12 by means of the cam portion s: and causes the armature 46 of the elec-2' tro-magnet 41 to be raised. The current source is indicated by RT. The raising of the armature causes the lever 32 to be turned and the two noses 40 and 4| to be released. At this moment the slay has already moved to some 4extent from the breast beam, so that the rack bar 26 can move frontwardly and the cutter blade 6 fixed on shaft 4 thus to be swung in a clockwise direction until the nose 53 comes into contact with guide 36. This position is shown in Fig. 5. During its swinging movement, the cutter blade 6 raises and carries frontwardly the weft threads n and o which extend from the edge of the fabric to the shuttle box compartments not in alignment with the race way, for instance compartments A and B (Fig. 8).

As above mentioned the nose 40 of the rack bar 26 was released simultaneously with the nose 4| of rack bar 28. 'I'he bar 26 could not move frontwardly by reason of the locking lever 34 which, in this position of the slay, lies against shoulder 43 (Fig. 5).

The cam portion :c of cam 1I now permits the switch 12 to open, thus cutting 'off the current. The electro-magnet armature 46 falls back and at the same time the locking lever 32 comes to lie once again in the path of the nose 40 of the rack bar 26. During the next stage, by way of example, the locking lever 34 is withdrawn from engagement with shoulder 43 of the rack bar 26 through the movement of the slay, by means of the draw hook.46. At the same time the shuttle S passes into compartment or cell C and the weft pis laid between the opened parts I5 and I3 and II and 6 of the cutter mechanism. Thereafter, as soon as the cam 1|, by its cam portion y, closes the switch 'I2 for a second time, the locking lever 32 releases the nose 40 of the rack bar 26. which can now swing out to the front since it is no longer impeded by the locking lever 34. The frontward movement of bar 26 causes a clockwise swinging movement of the finger I5, the weft p lying in the notch I8, being thereby raised and carried up to the clamp finger I3 where it is pressed, by means of the three-edged rib I6, into the corresponding groove I1 of said finger, the movement of the parts continuing until the Fig. 6 position is reached.

While the rack bar 26 is swinging forward, its incline 44 presses down the locking lever 33 which is thereby withdrawn from thev reach of the nose or shoulder 42 of the rack bar 21. The bar 21 can therefore also swing out frontwardly until its shoulder 52 comes into contact with the guide 30. The frontward movement of the bar 26 causes a clockwise swinging movement of the cutter blade I I and the latter cooperates with the blade 8 to cut the weft p held by the fingers I3 and I5 (Fig. '1 The weft thread remaining in the shed was, by movement of the fingers I3 and I5 drawn so far to the front as to be clear of the usual weft fork.

Weit-replenishment is now effected by known means not shown and at the same time shaft 69 continues to rotate and turns, by means of the cam 10, the lever 62 clockwise from the position I (Fig. 8) to position II against the action of a spring which is not shown. By this movement of lever 62 the stepped latch 54e, the pin 59e of which is at this moment between the guides 63' and 63", is turned anti-clockwise, so that the cooperating locking pawl 56e can, as shown, engage in the upper step of the latch.

Should it now occur that the replenished shuttle is not immediately picked back to the other side of the loom but remains for a longer time on the replenishing or exchange side, the pin 59e of the stepped latch 54c is removed, as the shuttle boxes fall from between the guides 63 and 63" and the pin of another latch, for instance, that of latch 54h is brought into engagement.

Position II of the lever 62 corresponds, for each shuttle box compartment, to a raised position of the respective stepped latch 54a, 54D or 54e, whilst the position I of the lever 62 corresponds to adropped stepped latch. In the position II of the lever 62, the switch 65 is closed, while in the position I it remains open. If now, by means of cam 14 on crankshaft 13, the switch 15 and thus the entire current circuit is closed, the same operation takes place as was previously initiated through the cam 1I by the closing of the switch 12,' while the gear shaft 69 is rotating, with the difference however that in this case the shuttle does not come from the feeler side, but from the replenishing side, and that it is not the exhausted weft end which is cut, but the new weft end. It is therefore quite immaterial after how many picks the replenished shuttle comes into action because the switch 65 is only closed when the pin of the raised stepped latch 54a, 54h or 54e corresponding to the shuttle box compart- 'on said lay,

ment, containing the replenished shuttle engages in the guides 63 and 63". The usual temple cutters, which serve the purpose of cutting the incoming weft, are, by means `of the invention rendered unnecessary.

When the rack bar 21 swings out to the right (forwardly), the nose 49 engages the short lever 50, causes the shaft 5I .to partially rotate and turns the lever 68 anti-clockwise out of position III (Fig. 8) into position IV. The lever 68 therefore presses against the projection 60a, 60h or 60C of the corresponding locking pawl 56a, 56h, or 56c concerned and turns said pawl clockwise so that it engages in the lower step of the cooperating stepped latch 54a., 54h or 54o.

I claim:

1. Thread-cutting mechanism for automatic weft replenishing looms having a lay, comprising cutting mechanism supporting means a shaft rockably mounted in said supporting means, a cutter, a pair of fingers coaxially mounted for lifting inactive weft and shifting `said weft out of reach of said cutter, a member cooperable with one of said fingers for clamping the weft to be cut, the other of said fingers being cooperable with said cutter for cutting said clamped weft, said fingers being fixed to said shaft to rotate therewith, said member and said cutter being independently rotatable about said shaft, and means for rotating said ngers, cutter and member for first lifting and shifting said inactive weft, then clamping the weft to be cut, and finally cutting the lastmentioned weft.

2. Thread-cutting mechanism for automatic weft replenishing looms having a lay, comprising cutting mechanism supporting means on said lay, a shaft rockably mounted in said supporting means, a cutter, a pair of fingers coaxially mounted for lifting inactive weft and shifting said weft out of reach of said cutter, a member cooperable with one of said fingers for clamping the weft to be cut, the other of said fingers being cooperable with said cutter for cutting said clamped weft, said fingers being fixed to said shaft to rotate therewith, said member and said cutter being independently rotatable about said shaft, means for rotating said fingers, cutter and. member for rst lifting and shifting said inactive weft, then clamping the weft to be cut, and fl nally cutting the last-mentioned weft, and cam. means forl synchronously operating said rotating means. i

KURT SCHWABE. 

